1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (c) 2015 Google, Inc
4 */
5
6 #include <common.h>
7 #include <dm.h>
8 #include <errno.h>
9 #include <log.h>
10 #include <linux/delay.h>
11 #include <power/pmic.h>
12 #include <power/regulator.h>
13 #include <power/tps65090.h>
14
tps65090_fet_probe(struct udevice * dev)15 static int tps65090_fet_probe(struct udevice *dev)
16 {
17 struct dm_regulator_uclass_plat *uc_pdata;
18
19 uc_pdata = dev_get_uclass_plat(dev);
20
21 uc_pdata->type = REGULATOR_TYPE_OTHER;
22 uc_pdata->mode_count = 0;
23
24 return 0;
25 }
26
tps65090_fet_get_enable(struct udevice * dev)27 static int tps65090_fet_get_enable(struct udevice *dev)
28 {
29 struct udevice *pmic = dev_get_parent(dev);
30 int ret, fet_id;
31
32 fet_id = dev->driver_data;
33 debug("%s: fet_id=%d\n", __func__, fet_id);
34
35 ret = pmic_reg_read(pmic, REG_FET_BASE + fet_id);
36 if (ret < 0)
37 return ret;
38
39 return ret & FET_CTRL_ENFET;
40 }
41
42 /**
43 * Set the power state for a FET
44 *
45 * @param pmic pmic structure for the tps65090
46 * @param fet_id FET number to set (1..MAX_FET_NUM)
47 * @param set 1 to power on FET, 0 to power off
48 * @return -EIO if we got a comms error, -EAGAIN if the FET failed to
49 * change state. If all is ok, returns 0.
50 */
tps65090_fet_set(struct udevice * pmic,int fet_id,bool set)51 static int tps65090_fet_set(struct udevice *pmic, int fet_id, bool set)
52 {
53 int retry;
54 u32 value;
55 int ret;
56
57 value = FET_CTRL_ADENFET | FET_CTRL_WAIT;
58 if (set)
59 value |= FET_CTRL_ENFET;
60
61 if (pmic_reg_write(pmic, REG_FET_BASE + fet_id, value))
62 return -EIO;
63
64 /* Try reading until we get a result */
65 for (retry = 0; retry < MAX_CTRL_READ_TRIES; retry++) {
66 ret = pmic_reg_read(pmic, REG_FET_BASE + fet_id);
67 if (ret < 0)
68 return ret;
69
70 /* Check that the FET went into the expected state */
71 debug("%s: flags=%x\n", __func__, ret);
72 if (!!(ret & FET_CTRL_PGFET) == set)
73 return 0;
74
75 /* If we got a timeout, there is no point in waiting longer */
76 if (ret & FET_CTRL_TOFET)
77 break;
78
79 mdelay(1);
80 }
81
82 debug("FET %d: Power good should have set to %d but reg=%#02x\n",
83 fet_id, set, ret);
84 return -EAGAIN;
85 }
86
tps65090_fet_set_enable(struct udevice * dev,bool enable)87 static int tps65090_fet_set_enable(struct udevice *dev, bool enable)
88 {
89 struct udevice *pmic = dev_get_parent(dev);
90 int ret, fet_id;
91 ulong start;
92 int loops;
93
94 fet_id = dev->driver_data;
95 debug("%s: fet_id=%d, enable=%d\n", __func__, fet_id, enable);
96
97 start = get_timer(0);
98 for (loops = 0;; loops++) {
99 ret = tps65090_fet_set(pmic, fet_id, enable);
100 if (!ret)
101 break;
102
103 if (get_timer(start) > 100)
104 break;
105
106 /* Turn it off and try again until we time out */
107 tps65090_fet_set(pmic, fet_id, false);
108 }
109
110 if (ret)
111 debug("%s: FET%d failed to power on: time=%lums, loops=%d\n",
112 __func__, fet_id, get_timer(start), loops);
113 else if (loops)
114 debug("%s: FET%d powered on after %lums, loops=%d\n",
115 __func__, fet_id, get_timer(start), loops);
116
117 /*
118 * Unfortunately there are some conditions where the power-good bit
119 * will be 0, but the FET still comes up. One such case occurs with
120 * the LCD backlight on snow. We'll just return 0 here and assume
121 * that the FET will eventually come up.
122 */
123 if (ret == -EAGAIN)
124 ret = 0;
125
126 return ret;
127 }
128
129 static const struct dm_regulator_ops tps65090_fet_ops = {
130 .get_enable = tps65090_fet_get_enable,
131 .set_enable = tps65090_fet_set_enable,
132 };
133
134 U_BOOT_DRIVER(tps65090_fet) = {
135 .name = TPS65090_FET_DRIVER,
136 .id = UCLASS_REGULATOR,
137 .ops = &tps65090_fet_ops,
138 .probe = tps65090_fet_probe,
139 };
140